Micropropagation, qualitative phytochemical analysis and antioxidant potential of Indigofera aspalathoides Vahl. ex. DC.

Indigofera aspalathoides Vahl. ex. DC., which belongs to the family Fabaceae, is popularly known as “Wiry Indigo”. In the present study, effective tissue culture protocol of I. aspalathoides was performed by callus induction from different explants such as node and root. MS medium supplemented with various concentrations and combinations of plant growth regulators was used. Interestingly, maximum callus induction from root (92%) and nodal explants (89%) was observed in MS medium amended with NAA (0.5 mg/L). Maximum shooting and rooting (95%) from nodal explants were observed on IBA (1.0 mg/L) + BAP (1.5 mg/L). MS medium supplemented with BAP (1.0 mg/L) showed maximum (91%) of multiple shoots from organogenic calli. Qualitative phytochemical analysis on methanolic extracts of both wild plant and calli indicated the presence of alkaloids, flavonoids, glycosides, carbohydrates, fixed oils, saponins, proteins and amino acids, phytosterols and phenols. The strong DPPH free radical scavenging activity of methanolic extract of callus showed IC₅₀ value of 20.26 μg/mL followed by wild plant 67.23 μg/mL when compared with that of standard ascorbic acid (8.24 μg/mL).